import Vue from 'vue'
import VueRouter from 'vue-router'
import Login from '../components/Login.vue'
import Home from '../components/Home.vue'
import Welcome from '../components/Welcome.vue'
import Users from '../components/user/Users.vue'
import Rights from '../components/power/Rights.vue'
import Roles from '../components/power/Roles.vue'

Vue.use(VueRouter)

const routes = [
  {
    path: '/',
    redirect: '/login'
  },
  {
    path: '/login',
    component: Login
  },
  {
    path: '/home',
    component: Home,
    redirect: '/welcome',
    children: [
      { path: '/welcome', component: Welcome },
      { path: '/users', component: Users },
      { path: '/rights', component: Rights },
      { path: '/roles', component: Roles }
    ]
  }
]

const router = new VueRouter({
  routes
})

// 挂载路由导航守卫
router.beforeEach((to, from, next) => {
  // to：将要访问的路径
  // from：代表从那个路径跳转而来
  // next：函数，表示放行。next()：直接放行；next('/path')：强制跳转到只当路径。
  if (to.path === '/login') return next()
  // 获取token
  const tokenStr = window.sessionStorage.getItem('token')
  // TODO token的合法性？如果通过特殊手段往sessionStorage中存入一个非法token，是否该导航守卫就失去了安全性？
  if (!tokenStr) return next('/login')
  next()
})

export default router
